The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 09, 2012
Filed:
Feb. 23, 2007
Graeme Moad, Victoria, AU;
Ezio Rizzardo, Victoria, AU;
San Hoa Thang, Victoria, AU;
Commonwealth Scientific and Industrial Research Organisation, Campbell, AU;
Abstract
The present invention is directed to a process for the cleavage of one or more starting polymers having thiocarbonylthio groups of the formula —S—(C═S)— into derived polymers having thiol end groups of the formula —SH. The process includes contacting the aforedescribed starting polymers, with a reagent having the formula XY, wherein Xis a nucleophilic group and Yis an extracting group that results in the starting polymer and a byproduct, which is then separated from the derived polymer by conventional separation processes. The derived polymer is free from any odor or color that is sometimes associated with the starting polymer and it can be used in making optical lenses, such as contact lenses.